Investigating whether coffee consumption during pregnancy is associated with late fetal death.

Women who drink eight or more cups of coffee a day are twice as likely as women who do not drink coffee to miscarry or have a stillbirth, a survey suggests.

While adjusting for other risk factors attenuated the association, the researchers think the results justify advice for pregnant women to drink no more than three cups of coffee a day.

Coffee drinking has been repeatedly associated with adverse pregnancy outcomes, and plausible mechanisms have been proposed to explain the link; yet some people still question its risks, explained lead author Bodil Hammer Bech from the University of Aarhus in Denmark.

To investigate, Bech and colleagues surveyed 88,482 pregnant women enrolled in the Danish National Birth Cohort about their coffee intake and potential confounding factors, at 16 weeks’ gestation.

After adjustment for confounders, the researchers found that the risk of fetal death was increased by 3 percent for women who drank one-half to three cups of coffee daily, compared with abstainers, by 33 percent for those who drank four to seven cups a day, and by 59 percent for women who drank eight or more cups daily.

No link was found between fetal death and tea or cola intake, however, indicating that some compound in coffee other than caffeine may underlie the observed effect.